The Universal Data and Serum Specimen Collection System will extend CDC's collaboration with the HTCs by assisting with the analysis of a uniform set of clinical data routinely collected by HTCs. These data are used to monitor the extent of complications of congenital bleeding disorders in the U.S. Specific measurements will be analyzed to evaluate the degree of joint disease. In addition, free testing of serum specimens collected annually from persons receiving care in the HTCs for the presence of blood borne pathogens will be offered by CDC to assist HTCs in monitoring related infections. After testing, the remainder of each serum specimen will be used by the CDC to establish a serum bank for possible future use in evaluating the safety of blood products used by these persons. Information from this system will be used by the Hematologic Diseases Branch of the CDC to assess the safety of the blood supply and to develop and monitor the effectiveness of intervention designed to address our mandate from Congress which is to reduce or prevent the complications of hemophelia. It is anticipated that the Universal Data and Serum Specimen Collection System will continue into the foreseeable future as the CDC continues its prevention activities for this population.